PREHEAT oven to 400° F. Grease or paper-line 12 muffin cups.
COMBINE flour, brown sugar, granulated sugar, baking powder, salt, cinnamon, baking soda and ginger in large bowl. Combine butter, pumpkin, eggs and buttermilk in medium bowl. Add to flour mixture, stir just until moistened. Spoon into prepared muffin cups, filling 3/4 full.
BAKE for 15 to 20 minutes or until wooden pick inserted in center comes out clean. Cool in pan on wire rack for 5 minutes; remove to wire rack to cool completely.